From Housatonic to Pathfinder

HMS Pathfinder sinks on 5 September 1914 after being torpedoed by German submarine U-21.

On 17 February 1864 the Confederate submarine H.L. Hunley sailed out of Charleston Harbor and sank the USS Housatonic using a spar torpedo. This was the first time a submarine sank a warship in combat, and proved the viability of undersea warfare. This mission has been rightly hailed as a milestone in naval warfare, and the Confederates deserve credit for innovation and bravery in planning and executing the attack. Yet it would be fifty years and seven months before a submarine claimed another victim – HMS Pathfinder 100 years ago today. Why?

Part of the problem was that the Hunley did not return from her mission. The loss of her crew meant that an incredible amount of expertise perished, knowledge that would have proved useful for future submariners. Lieutenant Dixon and his companions became the most experienced and successful submarine crew in history that night, and would remain so until the early 20th Century.

A bigger issue hampering submarine development was the Hunley’s primitive technology; using a hand crank as propulsion and a spar torpedo, her range and operational scope were necessarily limited. Even so, had the submarine survived she would have provided much study to experts, who could adapt her technology much like the U.S. Navy did after World War II studying surrendered U-Boats.

In many ways, the Hunley was like the Wright Flyer, demonstrating the possibilities of new technology but needing improvement to truly fulfill the potential. Improvement came with the advent of diesel and electric motors, enabling longer cruising ranges and torpedoes to be fired at a distance from the target. These advances, pioneered by John Holland and the Electric Boat Company in Connecticut, enabled the submarine to go far from friendly shores and engage the enemy at longer range and much less risk than the Hunley’s men faced in 1864. By 1914, over 400 submarines operated in 16 navies worldwide.

To show how far undersea warfare came in the half-century after 1864, consider the story of HMS Pathfinder, the next warship sunk by submarine on 5 September 1914. Sailing along the eastern Scottish coast on patrol, the German submarine U-21 tracked her on-and-off during the day. The U-21’s commander, Lieutenant Otto Hersing, decided to attack, and fired a torpedo at 3:43 PM from 1,500 yards away. It struck Pathfinder seven minutes later, causing internal explosions which sank her in four minutes. Of approximately 360 souls on board, 259 perished. U-21 returned to base a few weeks later after a successful patrol. Several more warships and merchant ships would fall victim to U-Boats in September and October 1914, before winter weather slowed operations.

A new era of warfare, started 17 February 1864 and improved on since, had arrived to stay.